An ink jet head including a plurality of ejection channels includes a number of piezoelectric elements which are capacitive-type actuators, as actuators for ejecting ink from each channel.
In the related art, as a method of generating a driving waveform for driving the piezoelectric elements, a method of switching a voltage to be applied to the channels with switches by providing a plurality of switches for each channel and generating a desired waveform in units of the channel is known. However, this method may lead to great power consumption, when an attempt is made to obtain sufficient ejecting speed.